codeccontext.h

wma定点解码算法

     * - decoding: unused
     */
    char *rc_eq;

    uint64_t error[4];

    /**
     * minimum MB quantizer.
     * - encoding: set by user.
     * - decoding: unused
     */
    int mb_qmin;

    /**
     * maximum MB quantizer.
     * - encoding: set by user.
     * - decoding: unused
     */
    int mb_qmax;

    /**
     * motion estimation compare function.
     * - encoding: set by user.
     * - decoding: unused
     */
    int me_cmp;
    /**
     * subpixel motion estimation compare function.
     * - encoding: set by user.
     * - decoding: unused
     */
    int me_sub_cmp;
    /**
     * macroblock compare function (not supported yet).
     * - encoding: set by user.
     * - decoding: unused
     */
    int mb_cmp;
    /**
     * interlaced dct compare function
     * - encoding: set by user.
     * - decoding: unused
     */
    int ildct_cmp;
#define FF_CMP_SAD  0
#define FF_CMP_SSE  1
#define FF_CMP_SATD 2
#define FF_CMP_DCT  3
#define FF_CMP_PSNR 4
#define FF_CMP_BIT  5
#define FF_CMP_RD   6
#define FF_CMP_ZERO 7
#define FF_CMP_VSAD 8
#define FF_CMP_VSSE 9
#define FF_CMP_CHROMA 256

    /**
     * ME diamond size & shape.
     * - encoding: set by user.
     * - decoding: unused
     */
    int dia_size;

    /**
     * amount of previous MV predictors (2a+1 x 2a+1 square).
     * - encoding: set by user.
     * - decoding: unused
     */
    int last_predictor_count;

    /**
     * pre pass for motion estimation.
     * - encoding: set by user.
     * - decoding: unused
     */
    int pre_me;

    /**
     * motion estimation pre pass compare function.
     * - encoding: set by user.
     * - decoding: unused
     */
    int me_pre_cmp;

    /**
     * ME pre pass diamond size & shape.
     * - encoding: set by user.
     * - decoding: unused
     */
    int pre_dia_size;

    /**
     * subpel ME quality.
     * - encoding: set by user.
     * - decoding: unused
     */
    int me_subpel_quality;

    /**
     * Maximum motion estimation search range in subpel units.
     * if 0 then no limit
     *
     * - encoding: set by user.
     * - decoding: unused.
     */
    int me_range;

    /**
     * frame_rate_base.
     * for variable fps this is 1
     * - encoding: set by user.
     * - decoding: set by lavc.
     * @todo move this after frame_rate
     */

    int frame_rate_base;
    /**
     * intra quantizer bias.
     * - encoding: set by user.
     * - decoding: unused
     */
    int intra_quant_bias;
#define FF_DEFAULT_QUANT_BIAS 999999

    /**
     * inter quantizer bias.
     * - encoding: set by user.
     * - decoding: unused
     */
    int inter_quant_bias;

    /**
     * color table ID.
     * - encoding: unused.
     * - decoding: which clrtable should be used for 8bit RGB images
     *             table have to be stored somewhere FIXME
     */
    int color_table_id;

    /**
     * internal_buffer count.
     * Dont touch, used by lavc default_get_buffer()
     */
    int internal_buffer_count;

    /**
     * internal_buffers.
     * Dont touch, used by lavc default_get_buffer()
     */
    void *internal_buffer;

    /**
     * global quality for codecs which cannot change it per frame.
     * this should be proportional to MPEG1/2/4 qscale.
     * - encoding: set by user.
     * - decoding: unused
     */
    int global_quality;

#define FF_CODER_TYPE_VLC   0
#define FF_CODER_TYPE_AC    1
    /**
     * coder type
     * - encoding: set by user.
     * - decoding: unused
     */
    int coder_type;

    /**
     * context model
     * - encoding: set by user.
     * - decoding: unused
     */
    int context_model;

    /**
     * slice flags
     * - encoding: unused
     * - decoding: set by user.
     */
    int slice_flags;
#define SLICE_FLAG_CODED_ORDER    0x0001 ///< draw_horiz_band() is called in coded order instead of display
#define SLICE_FLAG_ALLOW_FIELD    0x0002 ///< allow draw_horiz_band() with field slices (MPEG2 field pics)
#define SLICE_FLAG_ALLOW_PLANE    0x0004 ///< allow draw_horiz_band() with 1 component at a time (SVQ1)

    /**
     * XVideo Motion Acceleration
     * - encoding: forbidden
     * - decoding: set by decoder
     */
    int xvmc_acceleration;

    /**
     * macroblock decision mode
     * - encoding: set by user.
     * - decoding: unused
     */
    int mb_decision;
#define FF_MB_DECISION_SIMPLE 0        ///< uses mb_cmp
#define FF_MB_DECISION_BITS   1        ///< chooses the one which needs the fewest bits
#define FF_MB_DECISION_RD     2        ///< rate distoration

    /**
     * custom intra quantization matrix
     * - encoding: set by user, can be NULL
     * - decoding: set by lavc
     */
    uint16_t *intra_matrix;

    /**
     * custom inter quantization matrix
     * - encoding: set by user, can be NULL
     * - decoding: set by lavc
     */
    uint16_t *inter_matrix;

    /**
     * fourcc from the AVI stream header (LSB first, so "ABCD" -> ('D'<<24) + ('C'<<16) + ('B'<<8) + 'A').
     * this is used to workaround some encoder bugs
     * - encoding: unused
     * - decoding: set by user, will be converted to upper case by lavc during init
     */
    unsigned int stream_codec_tag;

    /**
     * scene change detection threshold.
     * 0 is default, larger means fewer detected scene changes
     * - encoding: set by user.
     * - decoding: unused
     */
    int scenechange_threshold;

    /**
     * minimum lagrange multipler
     * - encoding: set by user.
     * - decoding: unused
     */
    int lmin;

    /**
     * maximum lagrange multipler
     * - encoding: set by user.
     * - decoding: unused
     */
    int lmax;

    /**
     * noise reduction strength
     * - encoding: set by user.
     * - decoding: unused
     */
    int noise_reduction;

    /**
     * simulates errors in the bitstream to test error concealment.
     * - encoding: set by user.
     * - decoding: unused.
     */
    int error_rate;

    /**
     * MP3 antialias algorithm, see FF_AA_* below.
     * - encoding: unused
     * - decoding: set by user
     */
    int antialias_algo;
#define FF_AA_AUTO    0
#define FF_AA_FASTINT 1 //not implemented yet
#define FF_AA_INT     2
#define FF_AA_FLOAT   3
    /**
     * Quantizer noise shaping.
     * - encoding: set by user
     * - decoding: unused
     */
    int quantizer_noise_shaping;
} CodecContext;


/**
 * AVOption.
 */
typedef struct AVOption {
    /** options' name */
    const char *name; /* if name is NULL, it indicates a link to next */
    /** short English text help or const struct AVOption* subpointer */
    const char *help; //	const struct AVOption* sub;
    /** offset to context structure where the parsed value should be stored */
    int offset;
    /** options' type */
    int type;
#define FF_OPT_TYPE_BOOL 1      ///< boolean - true,1,on  (or simply presence)
#define FF_OPT_TYPE_DOUBLE 2    ///< double
#define FF_OPT_TYPE_INT 3       ///< integer
#define FF_OPT_TYPE_STRING 4    ///< string (finished with \0)
#define FF_OPT_TYPE_MASK 0x1f	///< mask for types - upper bits are various flags
//#define FF_OPT_TYPE_EXPERT 0x20 // flag for expert option
#define FF_OPT_TYPE_FLAG (FF_OPT_TYPE_BOOL | 0x40)
#define FF_OPT_TYPE_RCOVERRIDE (FF_OPT_TYPE_STRING | 0x80)
    /** min value  (min == max   ->  no limits) */
    double min;
    /** maximum value for double/int */
    double max;
    /** default boo [0,1]l/double/int value */
    double defval;
    /**
     * default string value (with optional semicolon delimited extra option-list
     * i.e.   option1;option2;option3
     * defval might select other then first argument as default
     */
    const char *defstr;
#define FF_OPT_MAX_DEPTH 10
} AVOption;

/**
 * AVCodec.
 */
typedef struct AVCodec {
    const char *name;
    enum CodecType type;
    int id;
    int priv_data_size;
    int (*init)(CodecContext *);
    int (*encode)(CodecContext *, uint8_t *buf, int buf_size, void *data);
    int (*close)(CodecContext *);
    int (*decode)(CodecContext *, void *outdata, int *outdata_size,
                  uint8_t *buf, int buf_size);
    int capabilities;
    const AVOption *options;
    struct AVCodec *next;
    void (*flush)(CodecContext *);
} AVCodec;

#endif /* CODECCTX_H */